Given the strains that area is likely to receive and also a willingness to keep the nice ginger gentleman from VOSA happy with a like-for-like repair, I'd suggest possibly using some 50mm x 50mm x 2mm steel box section, simply cut to length and then bolted in place with either one long bolt or two shorter ones?
For a fiver you should be able to get enough to do both sides?
http://www.ebay.co.uk/itm/Steel-box-...-/110639398816